Ultimate Weapons Codes

20th Position 8009CC06 C68F
21st Position 8009CC08 C69F
22nd Position 8009CC0A C6AF
23rd Position 8009CC0C C6BD
24th Position 8009CC0E C6C8
25th Position 8009CC10 C6D6
26th Position 8009CC12 C6E4
27th Position 8009CC14 C6F1
28th Position 8009CC16 C6FE
(Note: 1st You must start a new game with these codes or they will not work
2ndThese codes will place all nine characters ultimate weapons in 20-28slots in your weapons menu and 3rd, the supply of these items will never run out unless you turn off your gameshark)

Sources

Megaelixer

35th Position 8009CC24 C606

Master Materia, Long Range, and Mega All Codes

21st Position 3009CEB0 0030
22nd Position 3009CEB4 0049
23rd Position 3009CEB8 005A
24th Position 3009CEBC 000B
25th Position 3009CEC0 00OC
(Note: Like the items, the supply will never run out unless you turn yourgameshark off, which means you can equip all nine characters withtheir materia, however, you need to start the game over for the codes to work.